Eccentric piston pump or compressor



April 13, 1937.

J. o. HEINzE ECCENTRIC PISTON PUMP OR COMPRESSOR Filed Nov. 15, 1955 2Sheets-Sheet l INVENTOR. 0. JL/

April 13, 1937. .1. o. HElNzE 2,076,723

, ECCENTRIG PIsToN PUMP 0R COMPRESSOR Filed Nov. 15, 1955 2 Sheets-Sheet2 Patented Apr. 13, y1937' UNITED sTATEs PATENT oFFicE ECCENTRIC PISTONPUMP 0R COMPRESSOR.

Application November 1'5, 1935, Serial No. 49,913

2 Claims.

This invention relates to apump or compressor of the oscillatoryeccentric 'piston type.

In engines, pumps or compressors employing an eccentric oscillatingpiston, diiliculty has always 5 been experienced in preventing theproducts of combustion, fluid, or compressed air from leaking by thedividing wall or abutment to which the oscillating piston is pivotallyconnected from the intake to the exhaust side.

The present invention relates to a construction wherein the baille wallor abutment is so constructed as to obviate the possibility of leakagefrom the intake to the exhaust side of the piston and to accomplish thisdesired end it is found most desirable that the pivot member upon whichthe piston oscillates, be positioned within the cross sectional area ofthe piston and be firmly anchored in the walls of the cylinder. Thisalso facilitates the accurate location of the pin relative to the axisof the shaft and permits of the use of a bafiie wall of extended crosssectional area and provides a very rigid pivotal support for the piston,also permitting the employment of bearing members for the pivot pin,free to turn upon this pin as the piston oscillates and also with thepiston free to reciproca members which are positioned within atransverse slot or recess in the piston extending transversely thereofwith the ends of these bearing members abutting the end walls of thecylinder.

Further the present arrangement permits the use of an abutment wall ofextended thickness which may be formed at its inner end to closelyengage the bearing members which may be curved concentric with the axisof the pivot pin and thus insure against leakage past the abutment; andit is also an object to provide an arrangement wherein the abutment wallmay be provided with a shoe to engage the curved surfaces of the bearingmembers to make a tight joint, and this construction further lendsitself to providing adequate lubrication of the contact surfaces andalso adequate meansy may be provided for taking up wear caused by thesliding contact between bearing members and'walls of the piston slotl inrelation to which these members move as the piston oscillates within thecylinder.

With the above and other ends in view theA invention consists inthematters hereinafter set forth and more particularly pointed out in theappended claims, referencebeing had to the accompanying drawings, inwhich Fig. 1 is a transverse vertical section substantially upon theline I-I of Fig. 3, of a constructe relative to these bearing tionillustrative of an embodiment of the invention;

Fig. 2 is a sectional detail substantially upon the line `2--2 of Fig.l;-

Fig. 3 is a vertical section substantially upon the line 3-3 of Fig. 1,and

Fig. 4 is a cross sectional detail substantially upon the line 4-4 ofFig. 1.

As shown in the drawings, the pump or compressor comprises two cylindersplaced sideby side, each cylinder comprising an outer peripheral hollowring I and hollow disk-like heads or ends 2 and a common intermediatehead 3, the peripheral ring-shaped walls ci the two cylinders beingfirmly secured between the heads'2 and in abutting relation to theintermediate head 3, by means of a plurality of transverse bolts 4passing through the heads and peripheral ring walls to draw all intofirm abutting relation.

The outer peripheral rings I are each formed hollow to provide a watercirculating space between the outer wall of the ring and the inner Wall5 which forms the wall of each cylinder 6. Each of the ring members I isformed with a connecting rib or web I intermediate its ends, the spaceat each side of this rib forming a water space for the purpose ofcooling the cylinder and these spaces are in communication throughopenings 8 in the web at each side of a. thickened portion of the webwhich forms a stud 9 at oppo'- site sides of the casing or cylinderstructure and which studs are bored longitudinally to provide passagesI0 which open into the cylinders 6, the outer ends of these passagesbeing closed normally, by screw plugs II which may be removed for thepurpose of allowing any accumulation of fluid within the cylinders to bedrawn olf. The circular disk-like piston I2 within each cylinder is alsoformed hollow with a hollow hub portion I3 adapted to receive a ringsleeve I4 between which and the exterior surface of an eccentric I5,roller bearings I6 are interposed. The eccentric I5 for each piston issecured to a shaft I'I in any suitable manner as by a key I8 and thesee/ccentrics are positioned on the shaft-with the eccentric for onepiston having its large side extending in one direction from the shaftand the eccentric for the other piston extending in a diametricallyopposite direction.

Connecting the hub wall I3 of each piston with the peripheral wallthereof, are parallel Walls I9 and 20 which are spaced apart to form aslot 2I of extended Width therebetween, this slot opening through theends of each piston and extending inwardly to adjacent the hub ilthereof.

A tubular pivot pin 22 extends longitudinally of the slots 2| and whollywithin said slots and 5 through the heads 2 and 3, this tubular pivotmember being rigidly secured in place by nuts 23 on its outer endsengaging the outer sides of tain a tight joint between the surfaces ofthe block" and the surfaces of the wall I9 and shim 25, the expansiveforce of the springs 26 tending to rotate the piston to bring the walli9 into engagement with one side of the bearing block and exerting forceagainst the opposite side of the block. The ends of these half bearingsabut the end walls or heads 2 and 3 of the cylinders and the outer endsof the halves of the bearing block are formed concentric with the axisof the pivot pin 22 to closely fit at all times the inner end of anabutment member 21 having an outwardly extending rib or shank portion.21a to engage within a slot in the wall or ring member of the cylinderand is formed with shoulders to engage and closely t against the innercurved surface of the cylinder wall, the inner end of this abutment wall21 being formed concave to closely t against the convex outer ends orside of the two half bearings. This abutment 21 is also slottedlongitudinally to receive a bar 28 adapted to engage the curved outerside of the bearing members 24 and slide thereon as these members rotateslightly with the eccentric motion of the piston, and this bar or shoe28 is forced toward and into firm contact with the surface of thebearing block members by means of Vcoiled springs 29;'so that a verytight joint of extended width and length is provided between the bearingblock members 24 and the concaved inner end surface `of the wall orabutment 21. This abutment, because of its width and the close fit ofits lateral shoulders against the curved surface of the cylinder wall,provides a very rigid abutment and this abutment is further held againstmovement by one oi' the bolts 4 passing through the tongue or shankportion 21a of the abutment longitudinally thereof.

An inlet passage 30 is formed in the peripheral ring member forming theouter wall or walls of the cylinder, this inlet passage opening into.the cylinder adjacent one side of the abutment 21 and an outlet passage3| is provided in the wall at the opposite side of the abutment, thisoutlet being controlled by a poppet valve 32 so that back pressure willnot enter the outlet side of the cylinder.

By locating the pivot pin 22 within the slot 2| ofthe two pistons toextend across both pistons within the cross sectional area of thesepistons, a

very rigid pivot is provided upon which the pistons oscillate, and byproviding half bearing blocks in the slot in each piston upon this pivotpin, `these blocks completely fill the slot transverselyand provide anextended area of contact between the blocks and side walls of the slotsand also between the blocks and pivot pin and betweenthe blocks and theabutment wall 21 so that there is no possibility of leakage from theinlet to the outlet side of the piston, and a tight Joint is runnerinsured by providing the shoe 2l, which is spring pressed, against thecurved outer surface of the bearing members. The wedge strip or shim 2lfurther insures against leakage past the bearing members and thearrangement provides a free oscillatory movement of each piston.

As shown, the tubular pivot pin 22 may be utilized as a conduit forlubricant, one end thereof being closed by a screw plug 22 and a pipe 22inserted in its opposite end. Lubricant may thus be supplied to this pinand may escape laterally from its bore through holes bored radially andcommunicating with grooves formed in the side or contact surfaces of thebearing members 24 to provide oil conduits I4, lubricant also beingsupplied to the outer surface of the pivot member through these radialopenings. This film of oil supplied to the contact surfaces of thebearing members 24 also assists inpreventing leakage past these bearingmembers through the slot in which they are positioned.

Obviously changes may be made in the construction and'arrangement ofpartswithout departing from the spirit of the invention and I do not,therefore, wish to limit myself to the particular construction shown.

Having thus fully described my invention, what I claim is:-

l. A device of the character described comprising a cylinder having aperipheral wall and circular heads. a shaft mounted axially of saidcylinder, an eccentric on said shaft, a circular piston in said cylinderupon said eccentric, said piston having a slot opening through the endsand l35 periphery thereof, a pivot pin extending through said slot insaid piston longitudinally of said slot o and secured in the saidcylinder heads, half bearv.

ing members in said slot upon said pin for rota-V tion thereon with theoscillatory movement of said piston, the outer end of said pair ofbearing members being curved concentric with the axis of said pin andsaid pair being of alength equal to the length of the piston in which itis mounted, and an abutment wall projecting into said cylinder from theperipheral wall thereof, said abutment wall being of a thicknesssubstantially equal to the width of said slot in said piston andextending inward to adjacent the open outer sidey of said slot with itsinner end surface curved to'conform Vto the curvature of the outersurface of said pair of half bearing members, and means for yieldinglypressing one of said half bearings into close contact with one side ofsaid pivot pin and through the rotative adjustment of .saidpiston causedthereby, to press the other half bearing into rcontact with said pin andwith the opposite sidewall of said slot, said cylinder being formed withan inlet passage at-one side of said abutment wall and an outlet passageat the opposite side.

2. A device of the character described and as characterized in claim i,and wherein one side wall of said slot in said piston is formed by ashim member of plate form, and yieldable means is interposed betweensaid shim and one side wall of said slot to fome the said shim into firmcontact with the adjacent surface of one half bearing and through therotative adjustment of said piston caused by force applied to said shim,to force the opposite side wall of said slot into firm contact with thesurface of said other half bearing.

JOHN o. HEINzE.

